When Greenland was green was it underwater?

James Lewis:

James Hansen, NASA's True Believer in the global warming credo, has just been quoted by the Globe & Mail of Canada as follows:

"Prof. Hansen and his colleagues argue that rapidly melting ice caps in Antarctica and Greenland could cause oceans to swell several metres by 2100 - or maybe even as much as 25 metres, which is how much higher the oceans sat about three million years ago."

In an email to the Globe and Mail, Hansen writes

"If we follow 'business-as-usual' growth of greenhouse gas emissions... I think that we will lock in a guaranteed sea-level rise of several meters, which, frankly, means that all hell is going to break loose."

For all you non-metric folks, 25 meters equals 82 feet, or about as high as an eight-story building. "Several meters" is only about 9-15 feet. That's the wall of water that is going to drown all the coastal plains of the world if Hansen's predictions come to pass.

So you have a choice. You can either (a) hop in your car and head for the hills, or (b) consider the very real possibility that Dr. James Hansen has jumped the shark, and is rocketing upward fast enough to achieve orbital velocity. I personally think he has slipped the surly bonds of earth, as the poet says. NASA's Prophet of Doom is up, up and away, with a beautiful vrroom.

Dr. Hansen is a math modeler in the climate change game. How does he get Planetary Doom from a math model? It's very simple. You build in "positive feedback loops." That is, you look in the vast toolbox of climate variables to find just two factors that might reinforce each other in a catastrophic loop. For instance, carbon dioxide in the atmosphere might create a greenhouse effect, which causes more heating, which causes more water evaporation, which causes more greenhouse effect, which causes more heating, etc., etc. Keep looping that, and you raise world temps by just one degree Centigrade, so the polar ice caps melt and the oceans rise, up to 25 meters. See? It's easy.

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Wikepedia has a more modest sea level rise with similar resuts:

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The extreme north of Greenland, Peary Land, is not covered by an ice sheet, because the air there is too dry to produce snow, which is essential in the production and maintenance of an ice sheet. If the Greenland ice sheet were to completely melt away, sea levels would rise more than 7 m (23 ft)^[3] and Greenland would most likely become an archipelago.

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However, we know from history that the place got its name from being green with vegetation not green ice, so what was the sea level in 1200 A.D.? I think it is unlikely that it was 23 feet higher, much less 82 feet higher. You would think scientist would consider this in their models. While researchers have done core samples of the ice sheet there is not much discussion of the ancient sea level. I think there should be. If nothing else it would be a good test of the computer models that are predicting doom.